MEC 325CP Primer Seating Assembly - For 600 Jr., Sizemaster, Steelmaster Reloaders

The MEC 325CP Primer Seating Assembly is a genuine MEC (Mayville Engineering) replacement 3-piece priming station kit for single-stage shotshell reloaders. It contains the primer seating pad, primer seating cup, and primer seating spring - the three components that make up the complete primer seating function on a MEC single-stage press.

Designed as a direct factory replacement part, the 325CP fits the MEC 600 Jr., 600 Jr. Mark V, Sizemaster, and Steelmaster single-stage shotshell reloaders in all gauges. It seats primers cleanly across all standard grains, restoring reliable primer seating on a press that has worn out its original priming components. Whether you are rebuilding an older MEC single-stage or just keeping a spare on the bench, this is the correct OEM assembly.

Kit includes:

• Primer Seating Cup (part #326)
• Primer Seating Spring (part #330)
• Primer Seating Pad